According to Frank Bethwaite (author of 'High Performance Sailing',18'skiff, tasar, 59er designer, father of Julian Bethwaite, 49er designer), who has done extensive testing of his claims, the more highly polished a surface is the less drag it has. Laminar flow has significantly lower co-efficients of drag that turburlent flow - this is why modern airliners can fly as fast and efficiently as they do, they use laminar flow foils.
Any imperfections cause the flow to become turbulent thus increasing drag. In tests comparing highly polished centreboards with those sanded slightly to remove the shine, the highly polished boards came out in front every time.
To read an article on this very subject by Frank see:
http://www.bethwaite.com/bethwaite/publications/fastestfoils/fastestfoils_0987.htmCan waxing give a highly polished surface? If so then waxing would give a low drag surface, better than one that had been sanded. Frank found stainless steel polished to a mirror finish to be very low drag.
Rob.
